First, you will get preliminary results and then more details as the data is analyzed further. This information is available for Google as the company searches for keywords within your email.

So, the data is used for advertising but Google not only knows all the information in your metadata, but also knows what is contained in your email.

Now, if the NSA request data from your email account they will be able to see something similar to Immersion’ graph.

Also, you have to consider that NSA will probably see all of your email addresses and not just Gmail. Thus, the metadata retrieved is examined along with the metadata from everyone you’ve corresponded with.